Reduction Cell with Continuous Prebaked Anodes - A New Approach

摘要

In the 1950's, VAW developed the Erftwerk cell technology, which is characterised by a continuous prebaked anode system (CPA). The Elbewerk smelter, started up in 1972 and located in Stade, Northern Germany, is still operating and using this unique anode system at an amperage of 129 kA. Every year, 70,000 tonnes of aluminium are produced in one potline consisting of 204 pots. In the captive carbon plant, 12,700 prebaked anode blocks are made annually, which is equivalent to 30,000 tpy. The metal is cast into extrusion billets with diameters of between 135 and 350 mm. As a result of continuous improvements to process control and work practices, the Erftwerk cell has maintained its technical and economic competitiveness. This paper focuses on the particular advantages of this cell type. In contrast to the widely used discontinuous anode technology, the Erftwerk cell does not need anode changes or a large, expensive rodding shop. Furthermore, since the anode is completely consumed, there is no recycling of butts and no bath material treatment & handling. Plans are being devised to install point feeders and to automate all pot service operations. Other modifications, which may lead to reduced energy consumption, will also be discussed.